In order to increase the available interior space of recreational vehicles or trailers, slide-out rooms or sections can be made integral with the structure of the vehicle or trailer. During transit, these rooms can be retracted and stored in the interior of the vehicle or trailer with the exterior wall of the slide-out room approximately flush with the exterior of the vehicle or trailer. To use the slide-out room, the vehicle is first parked and leveled. The slide-out room is then slid outward from the vehicle to an extended position, increasing the interior space of the vehicle.
In prior art constructions, the floor of the movable slide-out room is typically supported above the floor of the portion of the room which remains stationary when the slide-out room is in its retracted position, and thus forms a portion of the usable interior floor while the vehicle is in transit. The floor of the movable slide-out room is higher than the floor of the stationary room section, which creates a step up from the stationary floor to the floor of the slide-out room when the slide-out room is placed in the expanded position. This step formed by the differential in floor height is undesirable, inconvenient, and may lead to injury from one unwarily tripping or stumbling thereover. Besides limiting the mobility of an occupant of the slide-out room, the step can cause difficulty in furniture placement and detract from the overall aesthetic appearance of the floor.
To address the problems created by this floor height differential, various slide-out structures have been proposed which allow the movable and stationary floors to have flush or coplanar upper surfaces at least when the slide-out room is in the expanded position. One such flat floor slide-out apparatus is disclosed in U.S. Pat. No. 5,491,933 issued Feb. 20, 1996 to Miller et al. In this patent, a sliding inner tube is movable laterally to pivot as the movable and stationary floor slide into the same horizontal plane during movement of the slide-out room section to its extended position. In seeking this position, however, the inner tube supporting the floor of the slide-out room section, which is dropped into flush engagement with the stationary floor, sags or tips downwardly due to the torque exerted by gravity in reaching a cantilevered position. This requires modification of the outer beam to provide a ramped surface, and also places undue stress on the drive element upon which the inner tube directly pivots.
Another factor in the design of an improved expandable vehicle is possible misalignment of the slide-out room during expansion. Chances for misalignment grow proportionately as the length of the slide-out room and the ensuing cantilevered weight exerted thereby increases. Any misalignment in the support mechanism for the slide-out room can lead to binding or skewing problems during movement of the slide-out room section between its extended and retracted positions.
It is an object of the present invention to provide a flat floor arrangement for a slide-out room section of a vehicle which is economical to manufacture and is dependable in use. It is another object of the invention to provide a flat floor arrangement which will ensure a low friction sliding operation without binding or misalignment problems. A further object of the invention is to provide a flat floor arrangement which involves cooperating movement of the support structure beneath the stationary floor and the floor of the slide-out room section.